Mortality of older persons living alone: Singapore Longitudinal Ageing Studies
Mortality rate per
Mortality of older persons living alone: Singapore Longitudinal Ageing Studies
Tze Pin Ng 0 1
Aizhen Jin 2
Liang Feng 1
Ma Shwe Zin Nyunt 1
Khuan Yew Chow 2
Lei Feng 1
Ngan Phoon Fong 1
0 Department of Psychological Medicine, Gerontology Research Programme, National University of Singapore , NUHS Tower Block, 9th Floor, 1E Kent Ridge Road , Singapore 119228 , Singapore
1 Department of Psychological Medicine, Gerontology Research Programme, National University Health System, Yong Loo Lin School of Medicine, National University of Singapore , Singapore, Singapore
2 National Registry of Diseases Office (NRDO) , Health Promotion Board , Singapore, Singapore
Background: We investigated the association of living alone with mortality among older persons, independently of marital, health and other factors, and explored its effect modification by age group, sex, marital status and physical functional disability. Method: Using data from 8 years of mortality follow up (1 September 2003 to 31 December 2011) of 2553 participants in the Singapore Longitudinal Ageing Studies (SLAS) cohort, we estimated hazard ratio (HR) of mortality associated with living alone using Cox proportional hazard models. Results: At baseline, 7.4 % (N = 189) of the participants were living alone, and 227 (8.9 %) died during the follow up period. Living alone was significantly associated with mortality 1.66 (95 % CI, 1.05-2.63), controlling for health status (hypertension, diabetes, chronic lung disease, stroke, heart disease, kidney failure, IADL-ADL disability and depressive symptoms), marital status and other variables (age, sex, housing type). Possible substantive effect modification by sex (p for interaction = 0.106) and marital status (p for interaction <0.115) were observed: higher among men (HR = 2.36, 95 % CI, 1.24-4.49) than women (HR = 1.14, 95 % CI, 0.58-2.22), and among single, divorce or widowed (HR = 2.26, 95 % CI, 1.24-4.10) than married individuals (HR = 0.83, 95 % CI, 0.30-2.31). Conclusion: Living alone was associated with increased mortality, independently of marital, health and other variables. The impact of living alone on mortality appeared to be stronger among men and those who were single, divorced or married.
Ageing; Living alone; Health status; Mortality
-
Background
Increasing numbers of older persons worldwide are
living alone. As much as 50 % of older women in
countries in Europe and North America live alone [1], and
although the figures are considerably lower in Asia at
less than 10 %, an increasing trend is unmistakable [2].
Living alone as a proxy measure of social isolation and
the lack of social support is of practical interest and
importance because of its potential negative impact on
health. A substantial body of evidence supports a link
between social isolation and emotional stress, adverse
health behaviour, poor access to health care, and
adverse health outcomes [3–8].
However, studies of the association of social isolation
with increased mortality have yielded mixed findings
[9–31]. Although some studies have found that living
alone or loneliness was associated with increased
mortality [9–19], other studies have found that living alone
did not have a detrimental impact on survival [20–23],
or paradoxically, was associated with decreased risk of
mortality [24–26]. In some population studies with
findings of null or negative associations, older persons
who live alone, compared to their counterparts who live
with others, were found to be in no worse physical
health and functional status [20, 23].
Older persons living alone tend to be over–represented
by those who are un–married, widowed or divorced, among
© 2015 Ng et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
whom negative health behaviours and status are more
frequent [32–34]. Notably, a meta–analysis of 53 independent
studies shows that being widowed, divorced, and never
married was significantly associated with greater risk of
death [35]. Not all studies of the impact of living alone on
mortality have controlled for the effect of marital status,
(17, 18) and therefore the independent effect of living alone
apart from marital status appears unclear.
Mixed findings of the impact of living alone on
mortality may reflect heterogeneity of effect across
different studies of populations that varied by age, sex,
economic and marital and health status. The significant
heterogeneity of effect due to (...truncated)